This invention relates to electromagnetic devices, such as stators for electric motors.
Hitherto in the manufacture of certain electromagnetic devices the electrical winding has had its conductors located in the electromagnetic core itself and the conductors have been interconnected by end windings located at the end faces of the core. Because of the desired sequence of connecting the conductors the end windings have been relatively complicated in construction and layout, extending circumferentially through many radians. Attempts have been made in the past to simplify the end winding construction and as illustrated in German Pat. No. 590949 a single layer winding is shown with the end windings formed as arcuate strips interconnecting substantially radially-extending leaders connected to the conductors. This arrangement is limited in its application to a single layer low-voltage 3 phase A.C. winding and the number of conductors in the core is limited in relation to the end windings which can only be accommodated successfully in groups.
In another prior proposal, known from French Pat. No. 1405924 the end windings are arcuate elements spanning a plurality of core slots and the winding is formed in two layers each layer being electrically separate from the other.
In a further prior proposal, known from U.S. Pat. No. 3,761,752 the conductors of the winding are helically disposed on a support structure and the end windings interconnect adjacent conductors in the winding layer.